[llvm-commits] [PATCH 01/20] Add DenseMapInfo for std::string

[David Greene]

Add a DenseMapInfo implementation for std::string.  This is useful
when mapping pairs that include a string component.
---
 include/llvm/ADT/StringExtras.h |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git oldinclude/llvm/ADT/StringExtras.h newinclude/llvm/ADT/StringExtras.h
index 5f5c041..d30e225 100644
--- oldinclude/llvm/ADT/StringExtras.h
+++ newinclude/llvm/ADT/StringExtras.h
@@ -16,6 +16,7 @@
 
 #include "llvm/Support/DataTypes.h"
 #include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/DenseMapInfo.h"
 #include "llvm/ADT/StringRef.h"
 #include <cctype>
 #include <cstdio>
@@ -165,6 +166,24 @@ static inline unsigned HashString(StringRef Str, unsigned Result = 0) {
   return Result;
 }
 
+// Provide DenseMapInfo for strings.
+template<> struct DenseMapInfo<std::string> {
+  static inline std::string getEmptyKey() {
+    std::string Empty("<<<EMPTY KEY>>>");
+    return Empty;
+  }
+  static inline std::string getTombstoneKey() {
+    std::string Tombstone("<<<TOMBSTONE KEY>>>");
+    return Tombstone;
+  }
+  static unsigned getHashValue(const std::string& Val) {
+    return HashString(Val);
+  }
+  static bool isEqual(const std::string& LHS, const std::string& RHS) {
+    return LHS == RHS;
+  }
+};
+
 } // End llvm namespace
 
 #endif
-- 
1.7.6